| 英文摘要 |
The purpose of this project in first year is to review and analyze the optimal release area of fish juvenile from literatures, to build standard operating procedure of release program, and to analyze the main elements calcium (Ca), strontium (Sr), barium (Ba), magnesium (Mg), manganese (Mn), sodium (Na) of black porgy otolith for those individuals cultured in hatchery-reared pools and never released to sea, recaptured marked individuals, and those individuals recaptured from sea without marking using Laser-Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICPMS). Moreover, the discrimination criteria were built by comparing between the otolith elements distributions of the individuals cultured in hatchery-reared pools and that of recaptured marked individuals. And then, those individuals recaptured from sea without marking will be well judged into released one or wild one by the criteria. The results showed that the optimal release area of fish juvenile shall be released to the area which the juvenile had been discovered; there had three bids for the fish juvenile, i.e., traditional fishes juveniles released bid, marking and released bid, and pro-culturing before release bid. Till now, 102 people and 1,094 individuals of black porgy have been investigated and recovered. Among them, 64 individuals came from the last year's releasing. The recovery rate was about 0.593?. The black porgy otolish of three cultured parents, three cultured juveniles, three released individuals, and ten individuals from sea without marking have been analyzed by LA-ICPMS. The results indicated that the Mg concentrations of otolith for the cultured and released juveniles showed a symmetrical single peak near core, which was about 5cm body length, like the invert V type, as well as, the Mn concentrations of otolith showed the lower values in central core area while high peaks in surrounding area, like the U type. Both two elements types of the cultured fish and released individuals were all different with that of wild fish. However there were no specific otolith patterns of Sr, barium Ba, and Na for the cultured and released juveniles. In the future, it is easy to discriminate the fish original from sea just by analyzing the distribution of elements in core area of otolith, and might be time-saving and low cost. |
